Gear pump



Dec. 30; 1947. H. H. HAIGHT 2,433,360

GEAR PUMP Filed Jan. 25, 1945 2 Sheets-Sheei 2 Z; lNvm-woz. Hiznn H. Hm?- MJAL, M

Patented Dec. 30, 1947 )uNi .1:o STATES PATENT OFFICE mix: 12:32:: 123 574352 8 Claims. 1

This invention relates to improvements in gear pumps of the pinion and ring gear type.

It is an object of the invention to provide an improved form of manifolding with aligned inlet and outlet ports; to provide. branch manifolds with staggered ends affording an adequate seal at each end of the rotor while still affording escape for liquid under compression. regardless of the direction of pump operation; to protect the bearing surface of the ring gear from being scratched by grit entrained with the liquid pumped; to provide novel and improved means for lubricating at least oneof the bushings with a portion of the material pumped; and otherwise to improve the strength and prolong the life of the apparatus as will more fully appear from the following disclosure of the invention.

In the drawings:

Fig. 1 is a side elevational view of the body as it appears when exposed by the partial removal of the cover, portions of the body and cover being shown in section.

' Fig. 2 is a view of the pump in transverse section'on the line 2-2 of Fig.1.

'Fig. 3 is a view of the pump in longitudinal section onthe line 3-3 of Fig. 1.

Fig. 4 is a view showing the inner face of the cover in elevation.

Fig. 5 is a diagrammatic section through the manifold. a

Like parts are identified by the same reference characters throughout the several views.

Thepinion 5 is mounted on shaft 6 and is provided with teeth I meshing with the teeth 8 of a ring gear 9 peripherally journaled in the casing 10 to rotate on an axis eccentric, to that of shaft 6. These parts are of generally conventional construction except that the outer periphcry of the ring gear 9 has its bearing surface interrupted at intervals by transverse grooves l I of generally axial extent. The marginal edges which extend about the sides of the ring gear Fig. 1, said tongues having relatively sharp flow dividing webs 2|, 22 as best shown in Fig. 2.

There is a gap between the tongues I9 and at or near the center of port l2, as indicated at '23 in.Fig..1. At this gap, the outer peripheral bearing surface of the ring gear 9 is exposed to the jetting action of flow entering or leaving port 12. At this gap'the flow is not divided, but directly, impacts and/or washes the outer pego ripheral surface of the ring gear, thereby tendof the ring gear at each side 'of the grooves ll are sharp and are constantly wiping the bearing surfacein the interior casing ID to tend to pick up in the grooves any grit which may enter the bearing. Means is provided for flushing the grooves H as will hereinafter be disclosed to carry such grit through the pump with a minimum of damage to the bearing surfaces.

The inlet and outlet points l2 and I3 of. casing l0 are aligned axially, this being frequently of great advantage in making installations. These ports open into manifolds of peculiar form best shown in Figs. 1 and 2.

' The manifold M divides into branches l5, i6,

ing to wash from the grooves ll successively exposed,at thegap, any grit which may have been picked 'up by such grooves from the inner bearing surface of the casing ill in the course of ring gear rotation.

As indicated in Fig. 2, the port l3 communicates with a manifold 24 similar to that already described and having branches 25 and 26 from which liquid entering or leaving the interdent-al spaces between the teeth 8 of ring gear 9 is guided by downwardly projecting tongue 29 and, upwardly projecting tongue 30, the respective tongues having sharpened dividing fins 3|, 32, as shown in Fig. 2.

In the elevation shown in Fig. l, the respective manifolds 25 and I5 may have some difference in form, as indicated in Fig. l. The manifold branch l5 extends materially closer to the vertical plane through the axis of shaft 6 than does the manifold branch 25. Manifold l5 has an arcuate surface 33 at substantially constant radius vfromth'e axis of shaft 6, while the manifold branch 25 terminates at an end wall 34 whichextends vertically from its point of nearest approach to the axis of shaft 6.

At the opposite or near side of the pump, the

' manifolding arrangement is reversed. It is the manifold 25 which extends closest to the vertical center line while the manifold 16 is shorter. At each end of the ring gear, there is a peripherally elongated bearing surface providing an adequate seal between the inlet 'and outlet manifolds. port l3 as between manifold branches l5 and 25 and is elongated toward port [2 as between However, this seal is elongated toward manifold branches 26 and I6. (See Fig. 5.) This tends to provide continuity and smoothness of pumping action without hammer, regardless of the direction in which the pump is operated and regardless of whether port l2 or port 13 comprises the inlet and which comprises the outlet In each direction of operation, there is one of the manifold branches available close to the vertical center line to receive the last liquid expressed from the interdental spaces-of the ring gear. Yet both ends of the ring gear have an adequate seal which could not be provided but for the staggered arrangement of the manifold branches as described.

The pump casing ID has an axial extension at 35 which provides a packed bearing for the driving end of shaft 6. Beyond the end of bushing I1, I provide a set of packing gaskets 36- between washers 31 and 38, the whole assembly being subjected to the pressure of a compression spring 39. Into the spring chamber, there is a lubricating connection from fitting 40.

Bushing I8, on the other hand, is wholly closed about the end of shaft 6 by the key 4|. Bushing i8 is located within the removable cover plate 42 of the casing. The liquid pumped may be used for the lubrication of the bearing provided by bushing l8. To this end, a duct 44 leads from manifold branch 26 through the metal of the cover' plate 42 to a point near the outer end of bush-' ing l8 where it communicates with'a radial duct 45 provided in the bushing and leading to the outer end of the bearing surface.

From the inner end of the bearing surface, a radial groove 46 leads through the surface of the bushing flange to a point of communication with the branch manifold l6. Thus, regardless of the direction of operation of the pump, one of the ducts 44 or 46 will communicate with the high pressure side and the other with the low pressure side to establish a pressure differential and to provide means whereby some of the liquid pumped may be led to and from the respective ends of the bearing surface provided by bushing l 8. Both bushings l8 and I! may be secured against rotation with the sha desired.

The crescent-shaped baffle 50, commonly used in pumps of this character, is desirably made a part of the removable closure 42 and projects therefrom into a counter bore at 52 in the pump casing whereby its inner or free end is rigidly anchored.

A pump manufactured as herein disclosed has strength, long life, relative freedom from bearing trouble, relatively high efficiency in pumping and relative freedom from noise.

I claim:

1. In a pump of the pinion and ring gear type, a casing having aligned ports and manifold branches leading from the respective ports and extending about the ends of the ring gear, diagonally opposite branches approaching close to the point of maximum compression and other diagonally opposite manifold branches terminating materially less close to the point of maximum compression, said casing providing bearing surfaces for each end of the ring gear which are rotatively staggered with respect to each other between the manifold branches at the respective ring gear ends.

2. In a pump, the combination with a ring gear and internal pinion gear meshing with the ring gear, said ring gear having teeth and interdental spaces from the ends of which said pinion is ring geartoward said point,

t by means of pins 41, 48, if'

adapted to displace liquid at the point of fullest mesh between the pinion and ring gear, of a casing within which the pinion and ring gear are operatively mounted for rotation, and means for driving one of said gears, said casing having bearing surfaces engaging the ends of the ring gear adjacent said point of fullest mesh and being provided with inlet and outlet ports having branch passages extending about both faces of the ring gear toward said point, the branch passages communicating with one of said ports being spaced from the branch passages communicating with the other of said port by said bearing surfaces of the casing, the bearing surfaces of the casing at opposite faces of the ring gear being angularly offset peripherally of the ring gear, a branch passage from one port leading close to the point of maximum mesh between said gears at one face of the ring gear, and a branch passage of the opposite port leading close to such point of maximum mesh at the opposite face of the ring gear.

3. In a pump, the combination with a ring gear and internal pinion gear meshing with the ring gear, said ring gear having teeth and interdental spaces from the ends of which said pinion is adapted to displace liquid at the point of fullest mesh between the pinion and ring gear, of a cas- '-ing surfaces engaging the ends of the ring gear adjacent said point of fullest mesh and being provided with inlet and outlet ports having branch passages extending about both faces of the the branch passages communicating with one of said ports being spaced from the branch passages communicating with the other of said ports by said bearing surfaces of the casing, said casing being provided internally with deflecting means before the respective ports having wedge-shaped fins for guiding liquid between the respective ports and the respective branch ,manifold passages communicating therewith.

4. In a pump of the character described, the combination with a ring gear having interdental spaces opening only to the end faces of the gear, of a pinion meshing with the ring gear and provided with teeth adapted at. the point of fullest mesh to displace liquid from said spaces, and means operatively mounting the ring gear and pinion for rotationand comprising a casing havsubstantially aligned inlet and outlet ports, branch manifolds leading from said ports about the respective ends-of the ring gear by communication with said spaces at the end faces of the ring gear, means projecting into said manifolds comprising sharp edge dividers for guiding flow between the ports and the respective manifold branches, said means terminating opposite said ports, to expose peripheral portions of the ring gear, and said ring gear portions being provided with channels of generally axial extent for collecting grit from the interior bearing surface of said casing, the flow through said ports being adapted to wash said channels at the points opposite said ports where the periphery of the ring gear and said channels are successively exposed.

5. The pump set forth in claim 4 in which diagonally opposite branch manifolds extend along opposite faces of the ring gear closer to the point of fullest mesh of the pinion with the ring gear than do the intervening manifold branches, said aesaseo casing having sealing surfaces abutting the end faces of the ring gear between the respective manifold branches and said surfaces being offset angularly at opposite faces of the ring gear.

6. In a, pump, the combination with an operatively meshing ring gear and pinion gear, of a casing operatively confining said gears and providing for the rotation thereof, said casing including a body portion having a gear cavity and a crescent-shaped recess opening toward said cavity together with a closure portion closing said cavity and provided with a crescent-shaped batlie spanning said cavity and having its end portions seated in said recess, said baffle intervening between a portion of the pinion and an internal portion of the ring gear.

7. In a pump of the character described, the combination with aring gear and pinion gear in operative mesh, of means providing bearinzs and manifold therefor including a casing having inlet and outlet ports, manifold leading from said ports into operative communication with the interdental spaces of the ring gear, a shaft upon r the baiiie means to flow through said ports wherewhich the pinion gear is mounted, a bushing for 1 said shaft carried by a portion of the casing, said bushing having an end face abutting the pinion gear, a groove in said face affording communication between one of said manifolds and the surface of said shaft adjacent said pinion, a duct leading from an opposite manifold toward the outer end of the haft, and a duct leading through said bushing from the first mentioned duct and to the outer end of the shaft whereby to subject spaced points of said bushing to differential pressures of the respective manifolds and to induce circulation through said bushing along said shaft.

8. In a pump, the combination with a ring gear and a pinion gear in operative mesh, and a shaft upon which the pinion is mounted, ofa casing providing bearings for the shaft and ring gear and having inlet and outlet ports and branch passages leading from each of said ports about 0 the ring gear toward the point of mesh of the pinion therewith, said ring'gear having interdental spaces opening endwise to said passages,

partition means within thecasing in bearing contact with the ring gear substantially at the point of mesh of the pinion therewith, said partition means separating the passages branching from one. of said ports from the passages branching from the other, and baflie means within the casing before each of said ports provided with deflecting surfaces for guiding flow between the I ports and the respective branch passages, the said baflle means having apertures opening through the ,casing bearing for the ring gear, and the ring gear having a peripheral bearing surface provided'with sharp-edged pocket means for picking up grit from the complementary bearing surface of the casing, the said sharp-edged pocket means being exposed through the apertures of by hydraulically to remove grit from said pockets.

' I-HRAM H. HAIGHT.

REFERENCES CITED The following references are of record in the file of this patent:

, UNITED STATES PATENTS Number Name Date 1,372,576 Tullman Mar. 22, 1921 1,709,580 Jensen Apr. 16, 1929 1,739,139 'Haight Dec. 10, 1929 1,768,818 Bock July 1, 1930 1,864,458 Nichols June 21, 1932 FOREIGN PATENTS Number Country Date 270,000 Great Britain May 2, 1927 

